Comments on: A whole star exploded, and no one told me?

By: Sanjaya

Sanjaya — Tue, 02 Oct 2012 23:34:45 +0000

Good to see such an amazing picture however, in what year did the star explode?
what was happening here on Earth when the star exploded?

By: Nathan

Nathan — Tue, 25 Sep 2012 19:53:44 +0000

Thanks for the explanation Neil – that makes sense now. I knew I was missing something easy in the explanation…

By: Neil Haggath

Neil Haggath — Tue, 25 Sep 2012 12:22:30 +0000

#1 Nathan:
When we say “it happened 5000 years ago”, we mean that’s when it was observed*, i.e. when its light reached Earth. The light by which we see it now has taken the same time to reach us, so we are now seeing the remnant as it was 5000 years after the supernova.
Which is, after all, what matters to us. What the remnant actually looks like now is irrelevant to us, because we can’t see it!

*I’m talking hypothetically there – as in, when the supernova’s light reached Earth, irrespective of whether or not any humans actually observed it! Astronomers can work out the remnant’s age, by studying its size and rate of expansion.

By: Messier Tidy Upper

Messier Tidy Upper — Tue, 25 Sep 2012 11:55:10 +0000

Interesting that a supernova so relatively recent is so obscure and little studied. Certainly wouldn’t have expected that.

Spose as (#6.) Pete Jackson suggests the southernly location may be its problem.

(Incidentally Australian aboriginal skylore is known to some extent for some groups & some aboriginal rock art depicts it although I’m far from an expert on this.)

@12. Chris :

Phil, the light from a distant supernova is on its way to Earth as we speak. Just to give you a heads up.

Well sure but from which star and celestial co-ordinates and when that’s what I want to know!

@11. Uncle Al : I know Betelguex / Betegeuse / Alpha Orionis has a variety of spellings but that’s a new one for me!

Cool as it’d be if Betelgeuse were to go supernova – as for instance James Kaler describes (linked to my name here) I’d kinda miss it in the sky if it goes.

Just as I’d miss Antares too – which right near its rival Mars for handy comparison over lats night or so!

So I’m personally hoping for Eta Carinae and definitely hoping to witness a supernova in my lifetime. 8)

*****

“…about 40 supernovae are exploding somewhere in the universe every second. However, light from most of these events won’t reach Earth for billions of years, if ever.”
- Page 73, “Ask Astro” column in ‘Astronomy‘ magazine October 2008.

By: Jeff S.

Jeff S. — Mon, 24 Sep 2012 22:56:29 +0000

In three months I’ll do my annual chore of teaching students EM, but I love it; still, it is so hard a subject, it is tough to learn. Still, EM is the most fascinating to me. Look forward to it again.

By: Jeff S.

Jeff S. — Mon, 24 Sep 2012 22:49:58 +0000

As it happens, I spent a solid chunk of my professional research career looking at supernovae remnants, the expanding debris after a star explodes. Everything about them is cool: the extraordinary energy released, the amazing beauty and symmetry they posses, the fact that many of the elements necessary for life are created in them

You are so correct. Electromagnetism in fact is the most fascinating force to me and is behind a lot of this; but of course gravity and nuclear are involved. It’s just that to life, EM is the most important force.

Life, non-life, supernovae, they all boil down to the same thing: this amazing quantum universe of which life is only a part.

By: Chris

Chris — Mon, 24 Sep 2012 22:45:31 +0000

Phil, the light from a distant supernova is on its way to Earth as we speak. Just to give you a heads up.

By: Uncle Al

Uncle Al — Mon, 24 Sep 2012 17:42:30 +0000

“But geez, next time, someone let me know before a decade passes, OK?” Betelgeus, 21 December 2012. Alas, its rotation axis does not point at Earth. A supernova’s optical shock wave oozes from its collapsed core through the star. A supernova’s ~10^58 neutrino pulse diffuses through the core implosion region, then propagates hard by lightspeed through the rest of the star. Super-Kamiokande will give a few hours advance warning if it is running. IceCube, not so much (sensitive for 10^11 to 10^21 eV neutrinos. Betelgeus’ thermal neutrinos will be a detector-wide, brief, correlated rise in noise rates. (It already happened some 600 years ago vs. local time. How can you doubt?)

Do Chanukah rather than Christmas this year. The Beiwe Festival (Sami people) has some nice butterworks. Chawmos (Kalash people) for fetishists. Dzon’ku ‘Nu (West African Papaws) for the giddy.

By: Terry

Terry — Mon, 24 Sep 2012 17:36:14 +0000

@1 I think the policy is that nothing happens until we see is; so if something happened 5000 years ago and it 6000 light years away; then that means that it ‘actually’ happened 11000 years ago.

By: Infinite123Lifer

Infinite123Lifer — Mon, 24 Sep 2012 17:36:12 +0000

A horrible new species of goo ball?

Who is that darn Sign Painter anywho?